using System;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		string input = "Foo! The quick brown fox. Bar! ";
		input = input + input + input + input; // repeated, each string takes about ~100ms
		string pattern = @"([a-z ]+)+!";
		var matchTimeout = TimeSpan.FromMilliseconds(150); // Decrease to ~100 to timeout
		try
		{
		    var result = Regex.Replace(input, pattern, "X",
		                                RegexOptions.None,
		                                matchTimeout);
		    Console.WriteLine("Result: " + result);
		}
		catch (RegexMatchTimeoutException ex)
		{
		    Console.WriteLine("Match timed out!");
		    Console.WriteLine("- Timeout interval specified: " + ex.MatchTimeout);
		    Console.WriteLine("- Pattern: " + ex.Pattern);
		    Console.WriteLine("- Input: " + ex.Input);
		}
	}
}

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